Improved apparatus for compressing air, gas



MPERS, PHOTO-LITHDGRAPHER, WASHINGTON. D C.

UNITED STATES PATENT OEEICE.

SALMON BIDVELL, OF PHILADELPHIA, PENNSYLVANIA.

IMPROVED APPARATUS FOR. COMPRESSING AIR, GAS, &.C.

Specification forming part of Letters Patent No. 44,9309 dated November 8, 1864.

To ail whom t ln/tty concern:

Be it known that I, SALMON BIDWELL, of Philadelphia, Pennsylvania, have invented an Improved Apparatus for Pumping Elastic Fluids; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

My invention consists of a series of barrels of different diameters, provided with pistons and valves, and arranged and operating in unison with each other, substantially as described hereinafter, so that the elastic iiuid compressed in the large barrels shall pass directly into the smaller barrels, to be there further compressed, as hereinafter set forth.

My invention is especially designed for the purpose of compressing air, gas, and other elastic iiuids to a great density, and for accomplishin g this end without interfering with the proper operation of the necessary valves.

In order tov enable others to make and use my invention, I will now proceed to describe its construct-ion and operation.

On reference to the accompanying drawings, which form a part of this specification, Figures l and 2 represent vertical sections of my improved pumping apparatus with the moving parts in different positions; Fig. 3, a sectional plan on the line l 2, Fig. l.

A is the lower barrel of' the apparatus, and to the exterior of this barrel are secured the two rods B and I3', which are connected together at the top by a cross-piece, c.

To the. interior of the barrel A is adapted a piston, a, formed at the lower end of the second barrel, D, to which is adapted the piston b of the third barrel, E, which receives the piston d of the fourth barrel, F, the latter receiving a pipe, G. at the lower end of which is a packing, y. This pipe is secured to the cross piece O, and the iianges e e on the upper end of the third barrel, E, are permanently secured to the rods B and B', which serve as guides for the flanges fjof' the second barrel, D, and for the iianges li IL of the fourth barrel, F, the two lastnamed barrels being connected together by the rods z' t', so that they can move simultaneously, a vertical reciprocating motion being imparted to them by any suitable mechanism. 4

It will be observed that each barrel, as well as the pipe G, is closed at the lower end, with the exception of the central opening, above which is a suitable valve.

As seen in Fig. l, the barrels D and F are in the act of rising simultaneously, in which case the fluid contained in the barrel D (the valve of the latter being closed) is being forced into the barrel E, the valve of which is open, at the same time the fluid in the barrel F is being forced into the pipe G, and a new supply of fluid is in the act of" entering the barrel A through the opening at the bottom of the same In Fig. 2 the barrels D and F are in the act of moving downward in a direction contrary to that illustrated in Fig. 1, so that the fluid previously admitted into the first barrel, A, is being forced into the barrel D while the fluid in the barrel E is passing into the barrel F. It will thus be seen that as the two barrels D and F reciprocate there will be an intermittent discharge oi' ii uid from the pipe G.

Ordinary pumps have been hitherto used for forcing compressed air or other elastic fluid into vessels or reservoirs and producing a high pressure th erein 5 but they are defective in their action, owing to the high pressure of the fluid contained in the barrels of the pumps, this compressed air interfering with the proper working of the necessary valves.

In my improved pumping apparatus the pressure in the first barrel, A, is compara tively light, while that in the smallest fourth barrel, F, has reached the desired density. Willen the piston a is at the limit of its downward movement, it is at a proper distance above the bottom ofthe barrel A to permit the valves to operate. A supply of compressed fluid must consequently remain behind as the piston commences its upward movement. The press ure of the iiuid, however, in the first barrel is so inconsiderable that it can havelittle or no tendency to interfere with the proper working of the valve. The iiuid in the fourth barrel, F, has been compressed to a greater density, but when that barrel has reached the limit ot' its upward movement and is about to return, the compressed iiuid between the bottom of the barrel and the end of' the pipe G is so small in quantity that its expansion, when the barrel begins to move down, cannot seriously interfere with the proper working of the valves. It will now be seen that by the use of' a series ot barrels having different areas and communicating directly With each other, and arranged and operating substantially in the manner described, the supply of elastic iuid can be compressed to a high density and forced into vessels or reservoirs with much greater uniformity of action and by less de- ;t'ect in the operation of the falves than by the usual air-pumps. It Will be also secu that the number of barrels may be increased Without departing from the main features of my invention.

I claim and desire to secure by Letters Patent- A series of barrels of diiferent diameters,

S. BIDWELL.

Witnesses:

CHARLES E. FOSTER, JOHN WHITE. 

